Spontaneous Nanoscale Wiggling in Cleaved WTe2

Abstract

Structural deformation of crystal lattices has emerged as a powerful pathway to engineer and boost electronic properties through lattice geometry. However, realizing ultrafine structural modulations remains challenging without external strain imposed by substrates, prestrain, or artificial patterning. Here, using scanning tunneling microscopy, we show that the cleaving process spontaneously induces nanoscale wiggling in 1T′-WTe2 without such external strain sources. Furthermore, scanning tunneling spectroscopy reveals pronounced electronic reconstruction and spatially resolved spectral modulations between the top and valley regions of the wiggling. Combined with first-principles calculations, our results show that this wiggling substantially modifies the local electronic structure relative to the unstrained flat region, suggesting electronic structure reconstruction driven by spontaneous lattice deformation. These findings establish spontaneous nanoscale wiggling as a self-formed structural modulation for local electronic-structure engineering in strain-sensitive low-symmetry layered materials.